When does IR35 apply?

Deciding whether IR35 applies involves the underlying nature of a worker’s relationship with a client being considered, in particular to examine whether the worker would in law have been an employee if they had not been engaged by the client via the PSC, in other words, whether the worker would have been an employee if they had contracted directly with the client to carry out the particular work concerned personally. This is not an easy test to apply. Each case depends on its own particular facts. Other tests must also be met for IR35 to apply but they are easier to apply in practice.

There is some case law on the subject but because each case depends on its own facts, the case law is of limited assistance.

As to how a right of a worker to substitute someone else to do any of the work for the client is relevant to deciding whether IR35 applies to a case, please read our Guidance Note (which you can see here).